Micropump dispensers are common in the personal care and cosmetics markets. A basic handheld pump dispenser (see FIG. 1) comprises an accumulator (101), a stem (102) and a spring (103) and typically dispenses between 50 and 500 μl of product (although some may dispense more or less) with each full stroke of the pump. The accumulator is a generally cylindrical body that holds the next dose of flowable product. The bottom of the accumulator has an inlet port (101a). Flowable product passes from a reservoir (110) through the inlet port, into the accumulator. A one way check valve (101c) associated with the inlet port allows product to flow into the accumulator, but discourages product or air from flowing in the opposite direction.
The top of the accumulator (101) is opened and a receives a lower portion of a hollow stem (102). The lower portion of the stem is shaped complementarily to the interior of the accumulator and is able to slide up and down in the accumulator, while maintaining liquid tight seal between the accumulator and the stem. The stem has an inlet port (102a) and an outlet port (102b). Product from the accumulator is able to flow into the inlet port of the stem, through the hollow stem, and out the outlet port of the stem. The outlet port of the stem may have a one way check valve (102c) associated with it, that allows product to flow out of the stem, but that discourages product or air from flowing in the opposite direction.
A spring (103) is disposed in the accumulator (101). The lower end of the spring is held motionless by resting against a fixed object, like the interior bottom of the accumulator. The upper end of the spring is movable and exerts a force against a lower portion of the stem (102). When the stem is in a raised position, the spring is minimally compressed. When a user presses the stem, the stem slides down into the accumulator, compressing the spring. As this happens, the one way valve (101c) of the accumulator closes off the inlet port (101a) of the accumulator and product is forced up the accumulator, through the stem and out the outlet port (102b) of the stem. When the user releases the stem, the stem slides out of the accumulator under the action of the expanding spring. As the stem slides out of the accumulator, the one way check valve (102c) of the stem closes and a vacuum is created within the accumulator. In response, product for the next dose is drawn from the reservoir (110), into the accumulator.
An actuator (111) seated on the top of the stem (102) and a dip tube (112) extending from the inlet port (101a) of the accumulator (101) into the reservoir (110), are additional components of some handheld pump dispensers, as well understood in the art. A housing (114) is used to secure the assembly of the accumulator (101) and the stem, as well as provide a means for attaching the pump to the reservoir. If the reservoir is not collapsible, then a vent (113) is provided to allow air from the ambient atmosphere to enter the reservoir. By “collapsible” reservoir, I mean that the volume of the reservoir shrinks as product is dispensed from the reservoir. A non-collapsible reservoir has a constant volume. By “atmospheric” pump, I mean a pump that allows the reservoir to draw air from the ambient atmosphere. Atmospheric pumps are typically used with non-collapsible reservoirs and typically have dip tubes. By “airless” pump, I mean a pump that does not allow the reservoir to draw air from the ambient atmosphere. Airless pumps are typically used with collapsible reservoirs and generally do not have dip tubes.
A collapsible reservoir may be implemented as a flexible container that shrinks as product is pumped from the flexible container. Alternatively, a collapsible reservoir may be implemented as a rigid container with a piston sliding therein. As product is pumped from the rigid container, the piston slides in the container so as to reduce the volume of the reservoir. These implementations are well known in the field.
Some micropumps have a locking feature that prevents the pump from dispensing accidentally. The locking feature sometimes takes the form of a rotating collar that registers opened and closed positions, such that the stem cannot be depressed when the collar is in the closed position. The rotating collar does not itself, cause the stem to move up or down.
There are also other types of packaging mechanisms common to the personal care industry, wherein a rotating collar causes a solid product to rise or fall. Lipsticks and deodorant sticks are common examples of this. Such mechanisms are not pump dispensers and are not useful for readily flowable media.
One of the more significant drawbacks of conventional micropump dispensers concerns the aesthetic. In personal care and cosmetics markets, the container on which the dispenser sits is usually relied upon to convey a particular aesthetic. Often the container is custom designed, at considerable expense. A conventional micropump dispenser is a substantial detriment to the visual appeal of the whole package. The stem and actuator protrude far above the container. The actuator accommodates a finger of the user and thus, must be of substantial size. Generally, the stem and actuator interrupt the design of the container and prohibit the design of the container from being carried through the top of the package.
In an effort to alleviate this problem, a decorative collar may be placed around the stem, to hide the stem and, perhaps a portion of the actuator. While this may hide the rather mechanical-looking stem, it does not really allow the design of the bottle to be carried into the top of the package. The stem and actuator are still a protruding distraction from the intended aesthetic. Another conventional method of dealing with this design problem is to use a so called, low profile pump; a pump that has been designed to be as short as possible, while still delivering a sufficient dose. But even low profile pumps do not completely solve the design problem because some portion of the pump still protrudes above the container. Furthermore, such low profile features are not typically available for lotion pumps.
Thus, a lotion pump wherein a stem and actuator do not detract from the aesthetic of the container and wherein the stem and actuator are easily blended into the design of the container, would be a great advantage over conventional lotion pumps. The present invention allows the design of the container to be applied through the whole package, without interruption.
Conventional lotion pumps are designed to dose product directly onto a target surface, such as a part of the body or onto a separate applicator, such as a hand, cloth or brush. Thus, lotion pumps do not usually have an integral applicator head which holds the dispensed product prior to application to the target surface. This is a disadvantage because a conventional lotion pump requires either a separate applicator or a it requires that the user get product on her hands. Getting product on the hands is often not desirable, as when the product is greasy or if the product colors the skin. A lotion pump with integral applicator head, such that a user would not have to get her hands dirty, would be an advantage over conventional lotion pumps. The present invention provides this useful feature.
Another feature of conventional lotion pumps, such as depicted in FIG. 1, is that the actuator orifice from which the dispensed product emerges is not stationary. During dispensing, the orifice is traveling downward. Thus, even if one wanted to associate an integral applicator head with a conventional lotion pump, the matter is complicated by the moving actuator orifice. This is unlike the present invention where the dispensed product emerges from a stationary orifice.
Another feature of conventional lotion pumps is a means for attaching the pump to a container of product. In FIG. 1, an example of this is the threaded closure (114). The pump is attached to and passes through the threaded closure. Often, the means of attachment is a snap fit or friction fit between the closure and the pump, such that the pump closure are readily capable of being separated.